Mechanisms of Dietary Fiber on Obesity-Related Disorders
Purpose of review: Dietary fiber is known to decrease risk of cardiovascular disease and obesity, but the most important mechanisms for fiber’s protective properties are debated. The purpose of this review is to summarize the most recent human studies that examine mechanisms on how dietary fiber decreases risk of obesity-related disorders.
Recent findings: Dietary fiber has effects throughout the digestive tract that decrease risk of obesity-related diseases. Soluble, viscous fibers are known to slow absorption of glucose and lipids and decrease serum cholesterol. Intake of dietary fiber can enhance satiety and reduce food intake at future meals. More recently, the importance of gut fermentation and the changes in the gut microbiota and metabolites have been linked to decrease risk for obesity-related disorders. Dietary fibers alter the gut microbiota and produce metabolites such as short chain fatty acids that may explain fiber’s role in obesity prevention and treatment. Dietary fiber encompasses a wide range of plant compounds, so conclusions that dietary fiber reduces or treats obesity related disorders must be considered by the type of fiber that was fed in the study.
Summary: It is well accepted that dietary fiber prevents and treats obesity-related disorders. Mechanisms for this protection include decreased absorption of macronutrients and enhanced satiety. Changes in the gut microbiota and short chain fatty acids are emerging mechanisms to explain why high fiber diets protect against obesity and have a role in obesity treatment.
